Heat transfer tube



May 12, 1931.

F. x. G OVERS HEAT TRANSFER TUBE Filed NOV. 5, 1928 mento':

Patented May 12, 1931 UNETD STATES PATENT OFFICE FRANCIS X. GOVERS, OF LAWRENCEVILLE, ILLINOIS, ASSIGNOR TO INDIAN REFIN'ING COMPANY, OF LAWRENGEVILLE, ILLINOIS, A CORPORATION OF MAINE I HEAT TRANSFER TUBE Application filed. November 5, 1928. Serial No. 317,300.

all peripherally uniform diameter, a bore of circular cross-section throughout its length and enlarged at its ends, and longitudinally extending exterior ribs, whose outer ends are within said periphery.

3. A heat-transfer tube as claimed in claim 1, in which the ribs are formed by removing the metal of the tube between the ribs.

In testimony whereof, I affix m signature.

FRANCIS X. OVERS.

This invention relates to tubes through whose Walls heat is to be transferred.

It is, of course, well known to provide tubes intended for this purpose with longitudinal- 1y extending fins to afford additionalsurface.

My invention relates to the particular construction of such a tube whereby it is easily made, and is so constructed that its end or ends can easily be secured into a tube-sheet, as by theexpansion methodor by electric welding. L

In the drawings:

Fig. 1 is a longitudinal section;

Fig.2 is an enlarged cross-section on plane 2, 2 of Fig. 1;

Fig. 3 is a sectional detail of a portion of atube-sheet, and

Fi 1 is a longitudinal section of a modi- 9 fied orm.

The tube is made from a length of pipe, advantageously seamless steel tubing, of a given substantially uniform outside diameter and bore. The end. portions of the bore may be enlarged as by boring out to form a chamber or chambers 1', 1 large enough to afford access to the expanding tool, by which the end or ends are expanded into the grooves 2, of an opening in a tubesheet 3.

Ribs 4, 4 are formed on the outside of the tube by cutting away the metal of the tube, between the end portions.v 'llie overall peripheral diameter of the tube is thus unchanged, but portions of the metal have been removed from the inside at the end or ends to adequately enlarge the bore for the purpose stated, and portions of the metal have .been removed from the outside to form the ribs, and thus largely increase the surface.

If it be preferred to electrically weld the tube into the tube-sheet, the enlargement or chamber 1 may be omitted, as shown in Fig. 4.

I claim:

1. A heat-transfer tube having an overall peripherally uniform diameter, a bore of circular cross-section throughout its length, and longitudinally extending exterior ribs whose outer ends are within said periphery, said ribs being of less length than the tube. 2. A heat-transfer tube having an over- 

